How to turn HDMI video off but keep audio on (slightly OT?)

Tomasz CEDRO tomek at
Thu Jul 15 09:44:18 UTC 2021

On Thu, Jul 15, 2021, 10:40 Tomasz CEDRO wrote:

> On Thu, Jul 15, 2021, 10:21 Aryeh Friedman wrote:
>> On Thu, Jul 15, 2021 at 4:09 AM Tomasz CEDRO wrote:
>>> there is /dev/dsp for each audio sink. have you tried cat /dev/random
>>> >/dev/dspN for N=0,1,.. and check wherher noise is produced over hdmi when
>>> monitor is enabled/disabled in/without WM?
>> Already tried that (should of mentioned it in the original post)
> then you may try to put monitor into some sort of dpms sleep mode (see
> xset s and xset dpms), so it does not power off, just keep audio out, that
> may depend on the particular device how it has power management implemented.
> this may contain some hints:

Audio and Video on HDMI are tied together. I would check if the monitor
itself has no power saving enabled on its own that may shut it down after
some (inactivity) time.

If this is the only HDMI output on the card I would simply increase dpms
power off time for instance to 4 hours of inactivity while keeping screen
saver/lock around 10/15 minutes.

If you have another HDMI output then you can buy HDMI to audio
cable/adapter they start at $2.5 at ebay and you stay independent of

The best way imo is to connect external USB Audio Card and stay independent
of HDMI at all. That assumes you have no audio card available already, or
no card with optical channel that you could connect directly to home cinema
audio instead using monitor output - most motherboards now provide audio
card even with spdif output :-)



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